Low capacity inductance coil



Dec. 18, 1934. w RUNGE 1,984,433

LOW CAPACITY INDUCTANGE COIL Filed July 5, 1953 INVENTOR WILHELM RUNGE svlvtggbow ATTORNEY Patented Dec. 18, 1934 UNITED STATES LOW CAPACITY INDUCTANCE COIL Wilhelm Runge, Berlin,

Teiefunlren Geaellschaft fiir graphic in. b. 11., Berlin, Germany,

tion of Germany assignor to Drahtlcse Telea'corpora- Application July 5, 1933, Serial No. 679,059 In Germany July 13, 1932 8 Claims. (Cl. 175-359) It is frequently necessary that in a coil, such as a coupling coil, different external electrostatic and inductive influences which are not uniformly distributed over the whole length of the coil, should produce the identical effect upon the two halves of the coil in order to become thus neutralized. For this purpose, the coil could be so wound that the midpoint of the winding is positioned at one end of the length of the coil, while the two halves of the winding, with the pitch of turns progressing in the same sense, are wrapped upon the bobbin or support with the result that the two ends of the coil are located at the opposite end of the length of the coil. However, when the chief desideratum is that the coil should possess as low as possible a self-capacitance, then the mode of winding just indicated is unserviceable.

According to the present invention, a mode of winding is employed for inductance coils which will measure up to all requirements as regards perfect compensation of extraneous influences as well as in reference to smallness of self-capacitance.

According to the invention, the two halves of the coil are sowound that the pitches of their turns progress in the same sense in reference to the middle of the coil, and that the two coil ends come to be placed in the same plane approximately, whereas the surfaces embraced by adjacent turns of the two coils are symmetric in relation to one another, while overlapping but partly.

What is best suited for this purpose is a coil support which consists of two annular or polygonal co-axial cylinders, the outer one thereof having two diametrically opposite slots, while the other cylinder surfaces may be either unbroken or else furnished with suitable cut-out portions, recesses, windows, and the like. The winding is disposed upon this support in such a way that one half of the coil is secured on one of the halves of the shell surface of the outer coil support formed by the said slots and the half of the inner coil support located diametrically opposite thereto, while the other winding half is secured on the two other halves of the coil support.

One exemplified embodiment of the basic idea of the invention is illustrated in the attached drawing in which, Fig. 1 illustrates a preferred type of bobbin used for winding the coil; and, Fig. 2 illustrates a top view of the coil and bobbin.

Fig, 1 illustrates a winding support consisting of two cylinders a and b, made of suitable insulation material. The outer support b has two slots cc, which are positioned diametrically opposite each other. The winding can be effected 5 in this manner that the middle of the coil lies at the end M of the slots and that the pitch .of the two winding halves is directed upwardly so that the two winding planes in the neighborhood of the top end of the support, come to be located approximately in one and the same plane. One half of the winding .101 which is indicated by solid lines, as shown-in Fig. 2, is brought upon the right-hand side b1 of the outer cylinder and the left-hand half c1 of the inner cylinder. The other coil half 1122 which is indicated by broken lines is supported by the left half b2 of the outer support and by the right half :12 of the inner supporter body.

The process of winding is effected preferably in this fashion that a start is made at the lowest point M of the slot 0 in that, for instance, nrst a loop of coil half ml is wrapped in counterclockwise sense, next a loop of winding half 102 in a clockwise direction, then again one turn of the half 101, and so on.

I claim:

1. Low-capacitance inductance coil, with this characteristic feature that, for the purpose of rendering the two winding halves perfectly symmetric in reference to outer electrostatic and inductive actions, these two halves are so wound that the pitch in reference to the coil middle progresses in like sense, and that the two coil ends are approximately located in the same plane, with the surfaces embraced by neighboring turns of the two coil halves being symmetric in relation to oneanother, though only partially overlapping.

2. Inductance according to claim 1, with this characteristic feature that its winding supports or bobbins consist of two co-axially arranged cylinders, the outer one of which is provided with two diametrical slots, one half of the coil being wound upon one half of the outer support formed by the said slots and upon the half of the inner support being located, diametrically opposite thereto, while the other coil half is wound upon the other halves of the coil support. 3. A low capacity coil structure formed of two symmetrical halves wound so that the pitch of both halves progresses in like sense with reference to the midpoint of the coil, the coil structurebeingformedofalternateturnsof each half, adjacent turns being only partially overlapping.

4. A coil structure as described in the next preceding claim wherein the two coil ends are 'l. A low capacity coil formed of two symmetrical halves, the two halves being wound so that the pitch of one half with reference to the center of the cofl progresses in the same sense as the pitch of the other half, the two coil ends being disposed in substantially the same plane.

8. A low capacity coil structure including a bobbin formed of two co-axially arranged cylinders one thereof being placed inside the other but spaced therefrom, the outer cylinder being provided with two diametrically arranged slots, the coil being wound on said. bobbin and adapted to form two symmetrical halves, said two halves being wound with respect to each other and with reference to the center of the coil so that their pitch progresses in the same sense, the two coil ends being disposed in substantially the same plane.

- WILHIELM RUNGE. 

